What are the best practices for drawing attention to specific parts of a design?
Search for Gestalt psychology: a branch of study that specializes in the "rules" of perception that you can employ to grab and hold attention. There is also an order of perception whereby some things are perceived before others.– StanAug 7, 2017 at 19:20
Here are some ways you can draw attention, roughly from the least subtle to the most:
- Movement - While effective, this should be used sparingly because it can grow distracting and annoying.
- Size - If a design element is larger than everything else, it will stand out.
- Color - Any deviation from the background colors or other colors used throughout the design will draw the eye.
- Contrast - A dark object on a light background will stand out. You should also consider logical contrasts in your subject matter, such as the following list: apple, orange, pear, bicycle.
- Text/Copy - Certain words draw the eye: Free, Secret, etc.
- Whitespace - Giving a design object enough whitespace around it will help differentiate it.
- Guiding the eye along a path - This can be as subtle as the direction a person's eyes are looking in a photograph or as blatant as an arrow.
Good summary by VirtuousMedia.
I would add shape. Things with harsh angles/corners draw attention more than those that are rounded.
However it's also important to keep in mind that things with sharp corners are less enjoyable to look at over time (some evolutionary thing about shark teeth maybe), so that technique is better used for things that need to be seen just once, not things where you want to draw attention and keep it indefinitely.
In my (limited) experience with graphic design there are a few key ways for drawing focus:
High contrast items tend to draw focus more than low contrast items.
Placement is a little more difficult as it depends on the media. For web design eyes tend to scan webpages in an "F" pattern.
As humans we still haven't lost our "look over there! it's a tiger: run!" instincts toward motion. A little bit of shaking/waving, and we've been distracted from whatever it was that we were paying attention to.